Re: changing mm->mmap_sem (was: Re: system call for process information?)

Rik van Riel
2001-03-18T10:48:41Z

On Sun, 18 Mar 2001, Mike Galbraith wrote:

> I gave this patch a try, and the initial results are extremely encouraging.
> Not only do I have vmstat (SCHED_RR) info in realtime with zero delays :))
> I also have a _nice_ throughput improvement. There are some worrisome
> warnings below along with the compile changes I made here, but for an
> initial patch, things look pretty darn wonderful.

[snip compile fixes .. integrated]

> VFS: Mounted root (ext2 filesystem) readonly.
> Freeing unused kernel memory: 196k freed
> Adding Swap: 265064k swap-space (priority 2)
> VM: Bad swap entry 00011e00
> VM: Bad swap entry 00058d00
> Unused swap offset entry in swap_dup 00058d00
> Unused swap offset entry in swap_dup 00011e00
> VM: Bad swap entry 00011e00
> VM: Bad swap entry 00058d00

Heh, I guess do_swap_page isn't too happy when multiple threads
of the same program take a page fault at the same address at the
same time.

I take it you were testing something like mysql, jvm or apache2 ?